[INFO] cloning repository https://github.com/nitros12/pyo3_rust_image_poc
[INFO] running `Command { std: "git" "-c" "credential.helper=" "-c" "credential.helper=/workspace/cargo-home/bin/git-credential-null" "clone" "--bare" "https://github.com/nitros12/pyo3_rust_image_poc" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnitros12%2Fpyo3_rust_image_poc", kill_on_drop: false }`
[INFO] [stderr] Cloning into bare repository '/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnitros12%2Fpyo3_rust_image_poc'...
[INFO] running `Command { std: "git" "rev-parse" "HEAD", kill_on_drop: false }`
[INFO] [stdout] caae8456a3332dbde1e038a767f92b291987da1c
[INFO] documenting nitros12/pyo3_rust_image_poc against 1.46.0 for beta-1.47-rustdoc-1
[INFO] running `Command { std: "git" "clone" "/workspace/cache/git-repos/https%3A%2F%2Fgithub.com%2Fnitros12%2Fpyo3_rust_image_poc" "/workspace/builds/worker-1/source", kill_on_drop: false }`
[INFO] [stderr] Cloning into '/workspace/builds/worker-1/source'...
[INFO] [stderr] done.
[INFO] validating manifest of git repo https://github.com/nitros12/pyo3_rust_image_poc on toolchain 1.46.0
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "read-manifest" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] started tweaking git repo https://github.com/nitros12/pyo3_rust_image_poc
[INFO] finished tweaking git repo https://github.com/nitros12/pyo3_rust_image_poc
[INFO] tweaked toml for git repo https://github.com/nitros12/pyo3_rust_image_poc written to /workspace/builds/worker-1/source/Cargo.toml
[INFO] crate git repo https://github.com/nitros12/pyo3_rust_image_poc already has a lockfile, it will not be regenerated
[INFO] running `Command { std: "/workspace/cargo-home/bin/cargo" "+1.46.0" "fetch" "--locked" "--manifest-path" "Cargo.toml", kill_on_drop: false }`
[INFO] [stderr]     Blocking waiting for file lock on package cache
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "metadata" "--no-deps" "--format-version=1", kill_on_drop: false }`
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] [stdout] 706f6e05cfd96c937d8ab6d8c7b7d4a13112a5221aea0de3ec27c5f2faea4a93
[INFO] running `Command { std: "docker" "start" "-a" "706f6e05cfd96c937d8ab6d8c7b7d4a13112a5221aea0de3ec27c5f2faea4a93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "inspect" "706f6e05cfd96c937d8ab6d8c7b7d4a13112a5221aea0de3ec27c5f2faea4a93", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "706f6e05cfd96c937d8ab6d8c7b7d4a13112a5221aea0de3ec27c5f2faea4a93", kill_on_drop: false }`
[INFO] [stdout] 706f6e05cfd96c937d8ab6d8c7b7d4a13112a5221aea0de3ec27c5f2faea4a93
[INFO] running `Command { std: "docker" "create" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/target:/opt/rustwide/target:rw,Z" "-v" "/var/lib/crater-agent-workspace/builds/worker-1/source:/opt/rustwide/workdir:ro,Z" "-v" "/var/lib/crater-agent-workspace/cargo-home:/opt/rustwide/cargo-home:ro,Z" "-v" "/var/lib/crater-agent-workspace/rustup-home:/opt/rustwide/rustup-home:ro,Z" "-e" "SOURCE_DIR=/opt/rustwide/workdir" "-e" "CARGO_TARGET_DIR=/opt/rustwide/target" "-e" "CARGO_INCREMENTAL=0" "-e" "RUST_BACKTRACE=full" "-e" "RUSTDOCFLAGS=--cap-lints=warn" "-e" "CARGO_HOME=/opt/rustwide/cargo-home" "-e" "RUSTUP_HOME=/opt/rustwide/rustup-home" "-w" "/opt/rustwide/workdir" "-m" "1610612736" "--user" "0:0" "--network" "none" "rustops/crates-build-env@sha256:d92eaeed33fa75130ca1ee6c8a01d1ffb62bac859dfdfb3450e3e5d1c0146529" "/opt/rustwide/cargo-home/bin/cargo" "+1.46.0" "doc" "--frozen" "--no-deps" "--document-private-items" "--message-format=json", kill_on_drop: false }`
[INFO] [stdout] 8646714acc79ed28d0f72933131282f3f370d2df205c30d7cdd48bd5a74bc3ce
[INFO] [stderr] WARNING: Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.
[INFO] running `Command { std: "docker" "start" "-a" "8646714acc79ed28d0f72933131282f3f370d2df205c30d7cdd48bd5a74bc3ce", kill_on_drop: false }`
[INFO] [stderr]    Compiling proc-macro2 v0.4.13
[INFO] [stderr]     Checking cfg-if v0.1.5
[INFO] [stderr]    Compiling proc-macro-hack-impl v0.4.0
[INFO] [stderr]    Compiling rayon v1.0.2
[INFO] [stderr]     Checking spin v0.4.9
[INFO] [stderr]    Compiling memchr v2.0.1
[INFO] [stderr]    Compiling regex-syntax v0.6.2
[INFO] [stderr]     Checking inflate v0.4.3
[INFO] [stderr]     Checking deflate v0.7.18
[INFO] [stderr]    Compiling lazy_static v1.1.0
[INFO] [stderr]    Compiling num-traits v0.2.5
[INFO] [stderr]     Checking gif v0.10.0
[INFO] [stderr]     Checking num-integer v0.1.39
[INFO] [stderr]     Checking crossbeam-utils v0.2.2
[INFO] [stdout] error[E0554]: `#![feature]` may not be used on the stable release channel
[INFO] [stdout]  --> /opt/rustwide/cargo-home/registry/src/github.com-1ecc6299db9ec823/spin-0.4.9/src/lib.rs:6:35
[INFO] [stdout]   |
[INFO] [stdout] 6 | #![cfg_attr(feature = "const_fn", feature(const_fn))]
[INFO] [stdout]   |                                   ^^^^^^^^^^^^^^^^^
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] error: aborting due to previous error
[INFO] [stdout] 
[INFO] [stdout] 
[INFO] [stdout] For more information about this error, try `rustc --explain E0554`.
[INFO] [stdout] 
[INFO] [stderr] error: could not compile `spin`.
[INFO] [stderr] 
[INFO] [stderr] To learn more, run the command again with --verbose.
[INFO] [stderr] warning: build failed, waiting for other jobs to finish...
[INFO] [stderr] error: build failed
[INFO] running `Command { std: "docker" "inspect" "8646714acc79ed28d0f72933131282f3f370d2df205c30d7cdd48bd5a74bc3ce", kill_on_drop: false }`
[INFO] running `Command { std: "docker" "rm" "-f" "8646714acc79ed28d0f72933131282f3f370d2df205c30d7cdd48bd5a74bc3ce", kill_on_drop: false }`
[INFO] [stdout] 8646714acc79ed28d0f72933131282f3f370d2df205c30d7cdd48bd5a74bc3ce